1. Field of the Invention
This invention is in the field of diagnostic assay using a protein or an antibody thereto.
2. Description of the Related Art
Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases of the central nervous system. They can be transmitted, inherited or occur sporadically and are observed in animals, e.g. as bovine spongiform encephalopathy (BSE) in cattle or scrapie in sheep, as well as in humans as Creutzfeldt-Jakob disease (CJD), Gerstman Straussler Scheinker syndrome, Fatal Familial Insomnia or Kuru. They have a long incubation period, leading to ataxia, dementia, psychiatric disturbances and death. Neuropathological changes include vacuolar degeneration of brain tissue, astrogliosis and amyloid plaque formation. The diseases are difficult to diagnose pre-mortem.
The cerebrospinal fluid (CSF) of CJD patients displays two additional polypeptide by two-dimensional polyacrylamide gel electrophoresis [Harrington, M. G. New England Journal of Medicine 315, 279 (1986), Hsich, G., Kenney, K., Gibbs, C. J., Lee, K. H. & Harrington, M. B. New England Journal of Medicine 335, 924 (1996).] The function of these 14-3-3 polypeptides remain unclear in TSE. They can be used in a pre-mortem test for CJD diagnostic evaluation, but have low specificity.
Monoclonal antibodies to the abnormal form of prion protein are available and can be used in an enzyme-linked immunoassay, as described in PCT Specifications WO 98/23962 and 98/32710 and Schmerr, M. J., the Beckman Coulter Pace Setter Newsletter 3(2),1-4 (June 1999), but these procedures have not yet been fully developed.
Development of new non-invasive blood CAD and BSE markers would help clinicians to establish early diagnosis.